Return-flue vertical boiler



(ModeL) 2 Sheets-Sheet 1.

P. P. DUNDON. I RETURN FLUE VERTICAL BOILER.

Patented Nov. 14, 1882.

SSSSSSSSSSSSS 2.

P. F. DUNDON.

RETURN FLUE VERTIGAL BOILER.

No. 267,407. Patented Nov. 14, 1882.

I ll i i II I l 3 1 1,",

NHE STATES PATENT Price.

PATRICK F. DUNDON, OF SAN FRANCISCO, CALIFORNIA.

RETURN-FLUE VERTICAL BOILER.

SPECIFICATION forming part of Letters Patent No. 267,407, dated November14, 1882. Application filed September 24, 1881. (Model.)

To all whom it may concern:

Be it known that I, PATRICK F. DUNDON, of the city and county of SanFrancisco, State of California, have invented a Return-Flue VerticalBoiler; and I hereby declare the following to be a full, clear, andexact description thereof.

M y in vention relates to certain improvements in that class ofsteam-boilers known as vertical or upright boilers; and it consistsindetails of the construction and arrangement of parts, substantially ashereinafter more fully set forth and claimed.

In the construction are certain details, all of which will be more fullyexplained by referring to the accompanying drawings, in which Figure 1is a vertical section of my boiler,

taken through as :0, Fig.3. Fig. 2 is a horizontal section taken through3 y, Figs. 1 or 3. Fig. 3 is a vertical section taken through to20,Fig. 1. Fig. 4 is avertical section through the boiler on line 2 z ofFig. 2.

A is the shell of my boiler,which stands in a vertical position, and hasone or more fireboxes or furnaces, B, formed in thelower part and at thesides of the boiler-shell, as shown. A portion of the fire-boxisrectangular in form and projects outside the shell of the boiler; butthe inner or rear end is made semicircular where it passes within thecurve of the shell of the boiler. If the boiler is oflarge diameter, twoor four, or more, of these fire-places or furnaces may be formed aroundthe shell, each extending a short distance toward the center, and thisgreatly increases the fuel and heating space. The crown-sheets C of eachof these fire-places which lie within the circumference of theboiler-shell are perforated to receive the lower ends of the tubes D,which extend up through the upper flue-sheet or top, E, of the boilerand convey the flame and productsof combustion from the furnaces to thispoint.

The exterior double shell G of the boiler extends upward above the heador flue-sheet E, and a top or casing, I, incloses the space betweenitself and the flue-sheet E,which is surrounded by the shell G so as toform a combustion-chamber, F, into which the products from the furnacesare led by the tubes D.

Other tubes, J, extend from the flue-sheet or -the products ofcombustion, which have thus passed through the water-space of the boilertwice, and from thence they are led into acasing, L, which surrounds theouter shell of the boiler and connects with the chimney orsmokestack M-or the chimne Y may connect directly with the chamber K, if preferred.

Steam drums or superheaters are supported above the chamber F at the topof the boiler, and have pipes connecting them with thesteamspace in theupper part of the cylindrical boilershell. superheaters in the form ofshort vertical cylinders, the bases of which lie below the top plate, I,of the chamber F, and consequently within the chamber, so that the heatof the flame passing up through the tubes D will strike the bottom ofthese superheaters.

By this construction I provide a vertical boiler in which the water issubjected to the action of the heat passing through it from the furnacesin small tubes, and also in returning through itin similartubes,whilethesteam within the drums H is exposed to the direct actionof the heat as it arises from the furnaces.

I am aware that vertical boilers have been constructed having a largecentral fire-place or furnace extending nearly to the top of the boilerand opening into an annular chamber of larger diameter, from which smalltubes descend through the space around the furnace to a chamber below,and I do not claim such a construction.

I am also aware that vertical boilers having centrally-located furnaceshave been provided with short horizontal'tubes connecting their upperportions with small tubes leading downward; but these furnaces are alllocated within the circumference of the shell of the boiler, andconsequently but one furnace to a boiler could be used. In my inventionthe furnaces are partly exterior to the shell of the boiler, and theymay therefore be multiplied as the size of the boileris' increased. Thewalls of the boiler extend above the upper tube-sheet,

In the present case I have shown these thus allowing the tubes to beentirely submerged, and keepingthe upper sheet, E, in contact withwater,which reduces the heat, the consequent expansion and contraction, andliability to leakage. The fire passes through and around the water inthe boiler three times before escaping, thus giving a largeproportionate heating-surface. The steam passes into the drums orsuperheaters, and is taken from them at such a distance above thewater-level that the water is not liable to foam or lift and the steamis thoroughly dried or superheated.

I am further aware that broadly it is not new to construct the inner orinclosed end of the furnace in a semicircular form.

Having thus described my invention,what I claim as new, and desire tosecure by Letters Patent, is-

1. In a vertical steam-boiler, the furnace or furnaces B, projectingoutside the shell of the boiler, and having that portion within the lineof the shell made semicircular, in combination with the fines 1),leading up within the shell of the cylinder from the crown-sheet of thefurnaces to an upper combustion-chamber at the the top of the boiler,substantiallyas herein described.

2. In a vertical steam-boiler, the furnace or furnaces B, projectingoutside the shell, and having their inner ends within the line of theshell and semicircular in form, the vertical tubes D, leading from thecrown-sheets up within the outer shell of the boiler to the uppercombustion-ch amber, F, in combination with the return-lines J,extending down behind and below the furn aces, and connecting thechamberFand the lower chamber, K, and the chimney, substantially asherein described.

3. The vertical boiler A, having the furnaces B partly exterior to thecircumference of the shell, the vertical flues D, leading from thecrown-sheets of the furnaces to the upper combustion-chamber, F, and thereturn-fines J, connecting the upper chamber, F, and the lower chamber,K, arranged below the furnaces, in combination with the exterioreasingor shell, L, connecting the chamber K with the chimney,substantially as herein described.

4. The vertical boiler A, having the furnaces B partly exterior to thecircumference of the shell, and the vertical tubes D, leading from thecrown-sheets of the furnaces to the chamber F above the boiler, incombination with the steam drums or superheaters H, connected with thespace within the main shell, and having their bases within the chamberF, and the cap or casing I, together with the tubes J, chamber K,exterior casing, L, and chimney, substantially as herein described.

In witness whereof I hereunto set my hand.

PAT tIOK F. DUNDON. Witnesses:

FRANK A. BROOKS, S. H. NoURsE.

